I guess if it's a very, VERY small amount of Krazy Glue, just on the underside of each foot or so, it should be all right, and should be easy to pull the figures back off without doing much damage. Perhaps another option is to use the Krazy Glue were used ONLY on the really difficult terrains (grass, etc.) and poster tack elsewhere?
Another risk of using super glue -- in the case of my own figures -- is that the stuff stains fabric REALLY BAD. I can trust you to be REALLY REALLY careful, can't I?
... the Findswoman